Optical Network Units (ONU's) are commonly used in Fiber-to-the-Curb (FTTC) communications systems. An ONU is typically located in a customer's neighborhood, and receives digital communication and data signals through optical fibers from a central office location. The ONU includes circuitry which converts the optical signals received on the fiber into electronic signals. These electronic signals are transmitted to customers on coaxial cables and/or single or multiple pair cooper conductors. The ONU also includes circuitry which allows electrical signals received from the customers to be converted to optical signals which are transmitted back to the central office on the optical fiber.
The positioning and installation of an ONU may be performed in a number of different ways. In neighborhoods or areas where overhead electrical and telephone lines are still used, the ONU can be mounted on a strand or on a supporting utility pole line. Connections may be then established from the source of the signals to the destination. In areas where lines are buried, it may be necessary to locate the ONU in an enclosure such that it is easily accessible for maintenance or repair purposes. Along with the ONU, other necessary elements of the FTTC system may be included within an enclosure, such as a splice case. The splice case contains and protects connections between cables entering and exiting the ONU. Also included in the enclosure are ends of necessary connecting electrical and fiberoptic cables. Some cables may be employed for the transmission or receipt of data signals, while others may be employed to receive power in order to operate the electronic components.